Effect of storage time with different lens care systems on in-office hydrogel trial lens disinfection efficacy: a multi-center study.

A combined prospective and retrospective study was conducted to evaluate the efficacy of in-office disinfection methods for hydrogel trial contact lenses. Two hundred and twenty-one trial contact lenses, disinfected by four different disinfection methods, were collected from seven Study Centers and cultured for microbial contamination after various storage periods. Negative and positive control lenses were included as an additional Center in this double-masked study. There was a significant difference in the incidence of microbial contamination among the Centers for all storage times (chi 2 p < 0.001). Contamination of trial lenses in Centers using thermal disinfection with preserved saline (SoftWear Saline) was negative and thermal disinfection with nonpreserved saline (LensPlus Saline) was 8.7%. Lens contamination in Centers using chemical disinfection was 13.6% with ReNu and 40.7% with OptiFree. The degree of contamination ranged from 90 colony forming units (CFU)/ml to over 10 million CFU/ml. Among the microorganisms isolated after the different disinfection methods were Alcaligenes xylosoxidans, Serratia marcescens, Moraxella phenylpyruvica, Enterobacter agglomerans, Pseudomonas stutzeri, and various gram-positive organisms. This study suggests that practitioners should redisinfect all inventory trial lenses at least once a month to minimize the risk of patient infection.